Treaty of Venlo

William V, Duke of the United Duchies of Jülich-Cleves-Berg had to relinquish his claims to Guelders and Zutphen in favour of the Holy Roman Emperor and King of Spain, Charles V of Habsburg.

However, States of Guelders exploited the confusion to declare independence and proclaim Charles II, son of Adolf, as the new Guelderian duke, with his aunt Catherine as regent.

This Guelderian War of Independence (1477–1499) ended in a Habsburg defeat, and Charles II firmly established his reign with the support of Kingdom of France.

William V eventually had to sue for peace in 1543, when all of Guelders, Zutphen and Jülich were occupied by Habsburg troops and France failed to come to his aid.

The Treaty of Venlo forced him to relinquish Guelders and Zutphen to Charles V, and he had to commit himself to suppressing the rise of Protestantism in his remaining lands of Jülich, Cleves, Berg, Mark and Ravenstein, keeping his population Catholic.